As a next-generation power generation system, a fuel cell module is known that generates electric power using a hydrogen-containing gas and an oxygen-containing gas. The fuel cell module includes a solid oxide fuel cell housed in a package thereof.
As the hydrogen-containing gas to be supplied to the solid oxide fuel cell, a fuel gas such as natural gas or petroleum gas, which are distributed commonly, is used. When a sulfur component contained in the fuel gas is supplied to a reforming catalyst or the solid oxide fuel cell, it degrades the reforming catalyst or the solid oxide fuel cell. Therefore, a reformer or the solid oxide fuel cell is supplied with a fuel gas that is desulfurized with a desulfurizer. In the desulfurizer, a catalyst for normal temperature desulfurization is generally used.
To reduce the desulfurizer in size, a hydrodesulfurization catalyst, which is higher in efficiency of desulfurization per volume than the catalyst for normal temperature desulfurization, is used. To use the hydrodesulfurization catalyst, a heat source of 200 to 400° C. is needed. Furthermore, when liquid such as water enters the hydrodesulfurization catalyst, the liquid may degrade the hydrodesulfurization catalyst when it vaporizes, decreasing the efficiency of desulfurization.
An objective of the present invention is to provide a fuel cell module in which the efficiency of desulfurization in a hydrodesulfurizer can be enhanced.